6x1070 rig - TDP 112w (60% for me) - OC +185/-500
Tpruvot ccminer 1.8.4
1745 MH/s
LBRY sp-mod #5
~1770 MH/s (+1.5%)
so basically the boost get eaten up by the fee

Also seeing something weird when on yiimp, miner crash each time the pool ask stats.
my result are different, i get 1600 with 1.8.4 and 150 core, but 1655 with sp mod, 3% faster
How much TDP (nvidia smi reading) do you use ? intensity ?
I redid some more test with
60/66/70/80% TDP, a wide range of intensity (19 to 24) overall about the same between ~1.5-1.8% increase versus ccminer 1.8.4